The present invention relates to information displays for use within a vehicle. More specifically, visual information displays are disclosed that are positioned behind an element, with respect to a viewer, such that the information displays, or portions thereof, are substantially invisible when not illuminated.
Recently, elements have been developed for rearview mirror assemblies that exhibit transflective characteristics. Light sources and/or information displays can be position behind the transflective element, with respect to the viewer, such that the light source or information display is substantially invisible when not illuminated. However, when illuminated while in operation, the light rays emitted by the information display and/or backlighting pass through the transflective element such that the related information is visible.
When the transflective feature is combined with an automatically variable reflective mirror, such as an electrochromic self-dimming mirror, the loss of intensity is substantial as the light rays emitted by the information display pass through the transflective materials and the electrochromic medium. A total of ninety-five percent loss in intensity can be expected when a backlit liquid crystal display is used.
Incorporating a backlit liquid crystal display, or a backlit information display of any type, with a transflective, variable reflectance, element has many inherent challenges in addition to overcoming attenuation of the intensity of the associated light rays. The transflective, variable reflectance, element may impact display color rendering, as well as, the focus, contrast, and viewing angle associated with the display. Specular reflections and color dispersion are also problematic when incorporating an information display with a transflective element.
What is needed is an information display design and an optimized transflective, directionally transmissive, preferentially reflective, partially reflective, preferentially absorbent, partially absorbent, preferentially transmissive or partially transmissive element to provide an aesthetically pleasing information display. Preferably, the information display is substantially invisible when not illuminated and produces focused, aesthetically pleasing, characters and/or graphical indicia when in operation.